FIELD OF THE INVENTION
The invention relates to a method and an apparatus for grinding and slotting friction products, and in particular integrally molded friction products, such as disk pads.
The invention relates particularly to a manufacturing environment known as J.I.T. (Just-In-Time), a manufacturing process which provides products efficiently at the time parts are needed in processing. Apparatus utilized in the J.I.T. environment are required to offer very quick changeover between different products and easy adaptability to various dimensional settings. They should be reliable and, advantageously, they should provide automatic loading and unloading features.
Reference will be had in the following to integral molding processes in the context of friction products. Integrally molded disc pads, for instance, are brake pads for motor vehicles which are produced in heated molds where the steel backing plate is directly adhered to the friction material. The adhesion and the molding of the material are effected by heat and pressure, normally assisted with an adhesive. The integral molding process is replacing the older process of forming the friction material and then drilling and attaching the molded friction pad to the steel back plate with rivets.
After the afore-described molding operation, the friction product is subjected to a finishing process, where it is fine-machined to a finished thickness typically within +/- 0.005" machining tolerance. Integrally molded disc pads now entering the finishing process require a new generation of machines. The older machines, for instance, could not handle the variety of steel back plates which often have pins and protrusions from the surface to facilitate mounting in the vehicle. In addition, a significant quantity of IM disc pads needed slotting across the friction surface to improve performance which required an additional feature either on the machine or a separate process.